Solar cell modules

Abstract

To provide a solar cell module that is highly rigid and can be manufactured at a low cost. [Solution] The solar cell module 1 comprises a front plate 2 and a back plate 3 arranged on the light-receiving side and the opposite side (anti-light-receiving side) of the solar cell unit 4 via a sealing material 6, and the back plate 3 is provided with a woven metal plate 30 made by weaving together a metal strip having a predetermined width W.

Description

Technical Field

[0001] The present invention relates to a solar cell module.

Background Art

[0002] Patent Document 1 below discloses a solar cell module provided with a metal foil, a metal mesh, or the like on a back plate on the side opposite to the incident light side. This solar cell module is a flexible solar cell module including a solar cell and a resin film laminated via a sealing material on the light-receiving surface side and the non-light-receiving surface side of the solar cell. Further, it includes a fire spread prevention sheet joined via a resin film to the non-light-receiving surface side of the solar cell, and the fire spread prevention sheet is made of a flexible sheet including any one of a metal foil, a metal mesh, and an inorganic fiber cloth. Therefore, it is described that in addition to suppressing the spread of combustion on the module surface to the back side (building side), the temperature rise of the module itself is suppressed, thereby improving the flame resistance of the module.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In automotive solar cell modules, for example, if mounted on the hood, a glass back panel would not meet regulations regarding head protection in the event of a collision. Furthermore, if the back panel is made of polycarbonate resin, the engine is located beneath the hood, and there are high-temperature components, raising concerns about reduced rigidity at high temperatures. While a metal back panel would address both of these issues, it increases manufacturing costs. Using a metal mesh for the back panel, as in the conventional technology described above, could potentially reduce manufacturing costs, but a small wire diameter would result in insufficient rigidity, raising concerns about reduced rigidity at high temperatures when mounted on the hood. Additionally, increasing the wire diameter to enhance rigidity could make it impossible to form the module in three dimensions.

[0005] This invention has been made in view of the above problems, and aims to provide a solar cell module that is highly rigid and can reduce manufacturing costs. [Means for solving the problem]

[0006] To solve the above problems, the solar cell module according to the present invention comprises a solar cell unit including at least one solar cell, and a front plate and a back plate arranged on the light-receiving side and the side opposite to the light-receiving side of the solar cell unit via a sealing material, wherein the back plate is provided with a woven metal plate formed by weaving together a metal strip having a predetermined width. [Effects of the Invention]

[0007] According to the present invention, by providing a woven metal plate as a structural element on the back panel, it is possible to provide a solar cell module that is highly rigid and can reduce manufacturing costs. [Brief explanation of the drawing]

[0008] [Figure 1] This is an enlarged cross-sectional view schematically showing the configuration of a solar cell module according to this embodiment. [Figure 2]This is a schematic plan view (a schematic cross-sectional view showing a cross-section taken along the line A-A in Figure 1) illustrating the structure of the woven metal plate of the solar cell module according to this embodiment. [Figure 3] This is a schematic plan view (a schematic cross-sectional view showing a cross-section cut along the line A-A in Figure 1) illustrating the structure of the woven metal plate of the solar cell module according to deformation form 1. [Figure 4] This is an enlarged cross-sectional view schematically showing the configuration of a solar cell module according to modified form 2. [Modes for carrying out the invention]

[0009] The embodiments of the present invention will be described in detail below with reference to Figures 1 to 4. Note that the embodiments described below are only one aspect of the present invention and do not limit the technical scope of the present invention.

[0010] The following embodiment describes an example in which the solar cell module 1 according to this embodiment is mounted on the hood of a vehicle. The solar cell module 1 has a curved plate-like shape. Therefore, it can be mounted on the hood of a vehicle in accordance with the similarly curved shape of the hood.

[0011] The solar cell module 1 has a surface plate 2 (Figure 1) made of a light-transmitting plate-like material on the uppermost layer of the hood. When sunlight or other light is shone on the solar cell module 1, the shone light passes through the surface plate 2 and reaches the inside of the solar cell module 1. This generates an electromotive force between the positive and negative electrodes of the solar cell module 1, and the generated electricity can be supplied to the vehicle or other devices.

[0012] Furthermore, the solar cell module 1 is thin and lightweight. Taking advantage of these characteristics, the solar cell module 1 can be mounted on various parts of the vehicle, not only the hood, but also the roof, fenders, doors, rear trunk, and other exterior panels, as well as the exterior panels or walls of buildings other than vehicles.

[0013] Figure 1 is a schematic enlarged cross-sectional view showing the configuration of the solar cell module 1 according to this embodiment. Figure 2 is a schematic plan view showing the configuration of the woven metal plate of the solar cell module according to this embodiment, that is, a schematic cross-sectional view showing a cross-section cut along line AA in Figure 1. Note that the solar cell module 1 is for vehicle mounting and is curved to correspond to the shape of the vehicle's hood, but in the cross-sectional view, it is shown as a flat plate for the sake of explanation. The solar cell module 1 comprises a front plate 2, a back plate 3, a solar cell unit 4 disposed between the front plate 2 and the back plate 3, and a sealing material 6 that seals the solar cell unit 4. In other words, the solar cell module 1 has the front plate 2 and the back plate 3 arranged on the light-receiving side and the opposite side (anti-light-receiving side) of the solar cell unit 4 via the sealing material 6.

[0014] The solar cell unit 4 has a plurality of substantially rectangular solar cells 5, which are arranged in a matrix with slight spacing between them in a plan view. Each solar cell 5 has a power generation element, electrodes, etc., and is curved in accordance with the curved shape of the solar cell module 1.

[0015] As previously described, the irradiated light passes through the surface plate 2 and then reaches the interior of the solar cell module 1. This irradiated light reaches the power generation elements (solar cells 5) and is absorbed, converting the energy of the irradiated light into electrical energy. Each power generation element (solar cell 5) is electrically connected by an interconnector (not shown), and current flows throughout the entire solar cell unit 4 via the interconnector.

[0016] The configuration of the solar cell unit, which is the power generation section of the solar cell module 1, is not limited to the configuration shown in the figure. For example, in this embodiment, a structure in which the power generation section is made up of a single solar cell unit is shown as an example, but a tandem structure in which the first and second solar cell units are arranged vertically may also be applied. Furthermore, the solar cells that make up the solar cell unit are not particularly limited, and any conventionally known solar cells can be used.

[0017] This embodiment is characterized by the structure of the back plate 3 of the solar cell module 1, and a structure body with high rigidity and capable of suppressing manufacturing costs is provided on the back plate 3 of the solar cell module 1.

[0018] The general manufacturing of the solar cell module 1 consists of a lay-up process of laminating each member, and then a lamination process of vacuum degassing and hot pressing with a vacuum laminating device (also called a laminator). Moreover, what is widely popular in manufacturing is flat-plate-shaped products for residential and industrial use, and cost reduction has been achieved through mass production effects and automated lines.

[0019] On the other hand, products for automobiles are three-dimensional-shaped products, and since the aforementioned solar cell manufacturing devices for residential and industrial use cannot be diverted, there is a lot of manual work and the manufacturing is costly.

[0020] Moreover, the lamination process for three-dimensional-shaped products also has the problem that cell cracking is likely to occur, the defect rate is high, and it also causes high costs in terms of manufacturing yield.

[0021] Therefore, by laminating in a flat-plate shape, products with low cost and good quality can be manufactured.

[0022] From the above, this embodiment proposes a structure of the solar cell module 1 (its back plate 3) that can be thermally bent (formed) in a three-dimensional shape after laminating in a flat-plate shape.

[0023] More specifically, the back panel 3 comprises a woven metal plate 30 and a sealing material 31 that seals the woven metal plate 30. In other words, the back panel 3 is configured as a laminated member in which the woven metal plate 30, provided as a structural element, is sandwiched between the sealing material 31. Furthermore, the back panel 3 has a plate-shaped insulating layer 32 on the solar cell unit 4 side (upper side) of the sealing material 31, in other words, between the woven metal plate 30 and the solar cell unit 4, and a plate-shaped resin layer 33 on the opposite side (lower side) of the sealing material 31 from the solar cell unit 4. The back panel 3 (and the sealing material 31 that constitutes it) is joined to the upper sealing material 6 via the insulating layer 32. That is, in this embodiment, the back panel 3 is configured in which the woven metal plate 30 is provided as a structural element, and a plate-shaped insulating layer 32 and a resin layer 33 are joined to the solar cell unit 4 side (sealing material 6 side) and the opposite side of the solar cell unit 4 side (sealing material 6 side) of the woven metal plate 30 via the sealing material 31.

[0024] As shown in Figure 2, the woven metal plate 30 is manufactured by weaving together metal strips (metal plates) having a predetermined width W so that they intersect at a predetermined intersection angle θ (approximately 90° in Figure 2). The woven metal plate 30 is three-dimensionally curved in accordance with the curved shape of the solar cell module 1.

[0025] For example, when applying a solar cell module 1 to the hood of a vehicle, the curvature of the design surface of the hood is determined by the vehicle's design, but the width W of the strips constituting the woven metal sheet 30 is set to match the curvature of the design surface of the hood. Therefore, the width W of the strips constituting the woven metal sheet 30 may be changed to match the curvature of the design surface to which it is mounted, for example, as shown in Figure 3. For example, the width W of the strips may be made smaller (narrower) in areas with small curvature, and larger (wider) in areas with large curvature. Similarly, the intersection angle θ of the strips constituting the woven metal sheet 30 may be changed to match the curvature of the design surface to which it is mounted.

[0026] Below, preferred examples of the materials or components and thicknesses of each component constituting the stacked structure of the solar cell module 1 of this embodiment are illustrated in order from the sunlight incident side. However, it goes without saying that the materials or components and thicknesses of each component are not limited to those described below. 1st layer: Surface plate 2 Material: PC (polycarbonate) resin, acrylic resin, ETFE (ethylene-tetrafluoroethylene copolymer) film, etc. (Preferably: PC resin) Thickness: 0.1-2mm (preferably 1mm) Second layer: Sealing material 6 (sealing material sheet on the upper part of solar cell 5) Material: EVA (ethylene vinyl acetate copolymer), polyolefin, ionomer, PVB (polyvinyl butyral), etc. (preferably: polyolefin) Thickness: 0.4~1mm (preferably 0.5mm) Layer 3: 5 solar cells Material: Silicon (Si) cell, perovskite element, etc. (Si cell preferred) Thickness: 0.1~0.2mm (preferably 0.18mm) Fourth layer: Encapsulation material 6 (encapsulation material sheet on the lower part of solar cell 5) Material: EVA, polyolefin, ionomer, PVB, etc. (Preferably: polyolefin) Thickness: 0.4~1mm (preferably 0.5mm) Fifth layer: Insulating layer 32 Materials: PC resin, acrylic resin, ETFE film, PET (polyethylene terephthalate) resin (preferably PET resin) Thickness: 0.1-2mm (preferably 0.5mm) Sixth layer: Sealing material 31 (sealing material sheet on the upper part of the woven metal plate 30) Material: EVA, polyolefin, ionomer, PVB, etc. (Ionomer preferred) Thickness: 0.1-2mm (preferably 0.5mm) 7th layer: Textile metal plate 30 Materials: Steel plate, aluminum plate, titanium plate, etc. (Preferably: steel plate, aluminum plate) Thickness: 0.1~1mm (preferably 0.2mm) Layer 8: Sealing material 31 (sealing material sheet on the lower part of the woven metal plate 30) Material: EVA, polyolefin, ionomer, PVB, etc. (Ionomer preferred) Thickness: 0.1-2mm (preferably 0.5mm) 9th layer: resin layer 33 Materials: PC resin, acrylic resin, ETFE film, PET resin (preferably PET resin) Thickness: 0.1-2mm (preferably 0.2mm)

[0027] The above components are laid up, and the solar cell module 1 is manufactured in a flat state using a vacuum laminating device (laminator). At this time, commonly available manufacturing equipment for glass modules can be used. After manufacturing the solar cell module 1 in a flat state, this solar cell module 1 is shaped (heat-bent) into a bonnet shape using a three-dimensional mold. At this time, the strips constituting the woven metal plate 30, which are provided as a structure within the back plate 3, are shaped (heat-bent) with slight misalignment, thereby enabling the manufacture of a three-dimensionally curved solar cell module 1.

[0028] In the above embodiment, the solar cell module 1 was manufactured using only one woven metal plate 30. However, as shown in Figure 4, for example, by arranging the woven metal plates in two layers (upper woven metal plate 30A, lower woven metal plate 30B) and using a hard ionomer resin or PVB resin with a Young's modulus of about 200 MPa for the sealing material 31 in between, shear deformation during module bending can be suppressed, and a generally known honeycomb structure can be realized. This makes it possible to achieve weight reduction while maintaining high bending rigidity.

[0029] As a preferred example of the configuration shown in Figure 4, the upper woven metal plate 30A and the lower woven metal plate 30B are made of aluminum and are thin sheets of about 0.1 to 0.5 mm thick, and the thickness of the intermediate sealing material 31 is preferably about 1 to 2 mm.

[0030] In summary, the solar cell module 1 according to this embodiment is a laminated member in which a woven metal plate 30 is provided as a structure on the back plate 3, and this woven metal plate 30 is sandwiched between sealing materials 31.

[0031] Furthermore, in process (1), a laminated structure is fabricated in a flat state using a vacuum laminating device (laminator), and then in process (2), the laminated structure is shaped into a bonnet hood design using a three-dimensional mold.

[0032] Preferably, when used for a bonnet hood, a laminated structure is adopted in which the bending rigidity is approximately the same as that of a steel plate t0.7.

[0033] Furthermore, to match the three-dimensional curvature of the bonnet hood, the structure of the woven metal sheet is such that the width W of the metal sheet is narrowed when the curvature is small, and widened when the curvature is large.

[0034] Although it is a metal sheet, the woven structure of the metal sheet makes it possible to create a three-dimensionally shaped structure. This allows for three-dimensional processing by heat bending after the lamination process in the flat sheet state.

[0035] Furthermore, since the above process (1) enables the production of solar cell modules in a flat (not three-dimensional) state, widely available manufacturing equipment can be used. Also, only one mold is needed for the above process (2). This reduces manufacturing costs.

[0036] Furthermore, while the vehicle's exterior is made of steel plate, achieving equivalent bending rigidity makes it possible to reduce head injuries in the event of a collision between a person and a vehicle.

[0037] Furthermore, for example, the curvature of the hood varies depending on the vehicle design, but the above-described woven fabric structure helps to reduce the stress on the power generation elements of the stacked solar cells.

[0038] The reason for this is that, for example, with a large strip width and small curvature, the bends between the strips become sharp, creating a load on the solar cells. This means that there is an optimal strip width that matches the curvature of the design. On the other hand, reducing the strip width reduces the load on the solar cells, but a smaller strip width increases the amount of material that needs to be woven in, which is not cost-effective in terms of manufacturing. Therefore, there is an optimal strip width that is desirable to be as large as possible (cost reduction), but also to be small for designs with small curvature (reducing cell load).

[0039] As described above, the solar cell module 1 according to this embodiment comprises a solar cell unit 4 including at least one solar cell 5, and a (translucent) surface plate 2 and a back plate 3 arranged on the light-receiving side and the opposite side (anti-light-receiving side) of the solar cell unit 4 via a sealing material 6, wherein the back plate 3 is provided with a woven metal plate 30 formed by weaving together a metal strip having a predetermined width W.

[0040] The back panel 3 is constructed by joining an insulating layer 32 and a resin layer 33 to the woven metal plate 30 on the side facing the solar cell unit 4 and the side opposite to the solar cell unit 4 via a sealing material 31. The insulating layer 32 and the resin layer 33 may be made of the same resin material.

[0041] The width W or crossing angle θ of the strip is set (changed) based on the curvature of the mounting surface for the solar cell module 1.

[0042] The solar cell module 1 has a curved shape.

[0043] The aforementioned solar cell module 1 is mounted on a vehicle (for example, on the hood).

[0044] According to this embodiment, by providing a woven metal plate 30 as a structural element on the back plate 3, it is possible to provide a solar cell module 1 that has high rigidity and can suppress manufacturing costs.

[0045] Furthermore, the present invention is not limited to the embodiments described above, and can be appropriately modified and altered without departing from the objective of the present invention. [Explanation of Symbols]

[0046] 1: Solar cell module, 2: Front panel, 3: Back panel, 30: Woven metal plate, 31: Encapsulating material, 32: Insulating layer, 33: Resin layer, 4: Solar cell unit, 5: Solar cell, 6: Encapsulating material, W: Band width, θ: Crossing angle

Claims

1. A solar cell unit including at least one solar cell, The solar cell unit comprises a front plate and a back plate, which are arranged on the light-receiving side and the side opposite to the light-receiving side via a sealing material, A solar cell module characterized in that the back panel is provided with a woven metal plate formed by weaving together metal strips having a predetermined width.

2. A solar cell module according to claim 1, The solar cell module is characterized in that the back plate is constructed by bonding an insulating layer and a resin layer to the solar cell unit side and the side opposite to the solar cell unit side of the woven metal plate via a sealing material.

3. A solar cell module according to claim 1, A solar cell module characterized in that the width or intersection angle of the strip is set based on the curvature of the mounting surface for the solar cell module.

4. A solar cell module according to claim 1, The solar cell module is characterized by having a curved shape.

5. A solar cell module according to claim 1, The solar cell module is characterized by being mounted on a vehicle.

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